linux-kernel - Re: [PATCH] bitops: simplify get_count_order

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Message-ID: <20200525091458.GK1634618@smile.fi.intel.com>
Date:   Mon, 25 May 2020 12:14:58 +0300
From:   Andy Shevchenko <andriy.shevchenko@...ux.intel.com>
To:     Wei Yang <richard.weiyang@...il.com>
Cc:     akpm@...ux-foundation.org, christian.brauner@...ntu.com,
        linux-kernel@...r.kernel.org
Subject: Re: [PATCH] bitops: simplify get_count_order_long()

On Sun, May 24, 2020 at 12:35:51PM +0000, Wei Yang wrote:
> These two cases could be unified into one.

Care to provide a test case which supports your change?

> Signed-off-by: Wei Yang <richard.weiyang@...il.com>
> ---
>  include/linux/bitops.h | 5 +----
>  1 file changed, 1 insertion(+), 4 deletions(-)
> 
> diff --git a/include/linux/bitops.h b/include/linux/bitops.h
> index 9acf654f0b19..5b5609e81a84 100644
> --- a/include/linux/bitops.h
> +++ b/include/linux/bitops.h
> @@ -206,10 +206,7 @@ static inline int get_count_order_long(unsigned long l)
>  {
>  	if (l == 0UL)
>  		return -1;
> -	else if (l & (l - 1UL))
> -		return (int)fls_long(l);
> -	else
> -		return (int)fls_long(l) - 1;
> +	return (int)fls_long(--l);
>  }

-- 
With Best Regards,
Andy Shevchenko